Air Quality Index Distribution

import matplotlib.pyplot as plt
import numpy as np
from matplotlib.colors import LinearSegmentedColormap

# Air quality data
np.random.seed(42)
n_readings = 9000

wind_speed = np.random.weibull(2.0, n_readings) * 8
wind_speed = np.clip(wind_speed, 0.5, 25)

base_pm25 = 150 / (1 + 0.3 * wind_speed)
pm25 = base_pm25 + np.random.exponential(15, n_readings)
pm25 = np.clip(pm25, 5, 300)

# Environmental theme
plt.style.use('dark_background')
fig, ax = plt.subplots(figsize=(10, 8))
fig.patch.set_facecolor('#081018')
ax.set_facecolor('#081018')

# Custom colormap - air quality green-blue
colors = ['#081018', '#0a2028', '#103038', '#184848', '#206058', 
          '#308068', '#40a078', '#60c088', '#80e098', '#a0f0a8', '#c0ffb8']
cmap = LinearSegmentedColormap.from_list('airquality', colors, N=256)

# 2D histogram
h = ax.hist2d(wind_speed, pm25, bins=50, cmap=cmap, cmin=1)

# AQI thresholds
ax.axhline(y=12, color='#60c088', linestyle='-', alpha=0.8, linewidth=2, label='Good (<12)')
ax.axhline(y=35.4, color='#ffa502', linestyle='--', alpha=0.7, linewidth=1.5, label='Moderate')
ax.axhline(y=55.4, color='#ff8c00', linestyle=':', alpha=0.7, linewidth=1.5, label='Unhealthy Sensitive')
ax.axhline(y=150.4, color='#ff6b6b', linestyle='--', alpha=0.7, linewidth=1.5, label='Unhealthy')

# Dispersion model
x_curve = np.linspace(0.5, 25, 100)
y_curve = 150 / (1 + 0.3 * x_curve)
ax.plot(x_curve, y_curve, '-', color='#a0f0a8', linewidth=2.5, alpha=0.8, label='Dispersion Model')

# Styled colorbar
cbar = plt.colorbar(h[3], ax=ax, pad=0.02, shrink=0.85)
cbar.ax.set_facecolor('#081018')
cbar.set_label('Reading Count', fontsize=11, color='#a0e0a8', labelpad=10)
cbar.ax.yaxis.set_tick_params(color='#a0e0a8')
cbar.outline.set_edgecolor('#205040')
plt.setp(plt.getp(cbar.ax.axes, 'yticklabels'), color='#a0e0a8', fontsize=9)

ax.set_xlabel('Wind Speed (m/s)', fontsize=13, color='#a0e0a8', fontweight='600', labelpad=10)
ax.set_ylabel('PM2.5 (ug/m3)', fontsize=13, color='#a0e0a8', fontweight='600', labelpad=10)
ax.set_title('Air Quality vs Wind Speed', fontsize=16, color='white', fontweight='bold', pad=20)

ax.tick_params(colors='#80c088', labelsize=10, length=0)
for spine in ax.spines.values():
    spine.set_visible(False)

ax.legend(loc='upper right', fontsize=8, facecolor='#102028', edgecolor='#205040', 
          labelcolor='#a0e0a8', ncol=2)
plt.tight_layout()
plt.show()